Military Time Converter

How to convert between military and 12-hour time

From 12-hour to military:

1. Drop the colon and the AM/PM label, keeping the minutes as the last two digits.
2. For AM times, pad the hour to two digits: 7:05 AM → 0705. The one exception is 12 AM, which becomes 00 — so 12:30 AM is 0030.
3. For PM times, add 12 to the hour: 5:30 PM → 17 → 1730. The exception is 12 PM, which stays 12 — so 12:45 PM is 1245.

From military to 12-hour:

1. Split the four digits into hours (first two) and minutes (last two): 1730 → 17 and 30.
2. If the hour is 0, it's 12 AM. If it's 1–11, it's AM as-is. If it's exactly 12, it's 12 PM. If it's 13–23, subtract 12 and mark it PM: 17 − 12 = 5, so 1730 is 5:30 PM.

How the math works

Both clocks describe the same underlying quantity: minutes elapsed since midnight. The 24-hour clock states it directly — 1730 means 17 full hours plus 30 minutes, or 1,050 minutes into the day. The 12-hour clock wraps that count at noon and restarts the hour numbers, using AM and PM to record which half of the day you're in. Conversion is therefore just adding or subtracting 12 hours (720 minutes) for the PM half, with two special cases at the wrap points: hour 0 displays as 12 AM, and hour 12 displays as 12 PM. This converter parses whatever you type into a minutes-since-midnight count, then renders that single number in both notations, which is why the two boxes can never disagree.

Worked example: what is 1730 in regular time?

Take 1730. The first two digits are the hour, 17; the last two are the minutes, 30. Since 17 is greater than 12, subtract 12: 17 − 12 = 5, and the time is in the PM half of the day. So 1730 military time is 5:30 PM. Spoken aloud it's "seventeen thirty." Going the other way: 8:15 AM is before noon, so the hour stays 8 — pad it to two digits and drop the colon to get 0815, read as "zero eight fifteen."

Military time chart (complete 24-hour reference)

Reading military time out loud

Three habits separate military time from an ordinary 24-hour clock display. First, it's written without a colon: a wall clock might show 17:30, but a duty roster writes 1730. Second, every time is exactly four digits, so morning hours carry a leading zero — 0600, never 600. That zero is spoken too: 0600 is "zero six hundred," and some services say "oh six hundred." Third, times on the full hour are read as "hundred," not "thousand" — 0900 is "zero nine hundred," 2000 is "twenty hundred." When there are minutes, you simply read both pairs of digits: 1730 is "seventeen thirty," and 0905 is "zero nine zero five." The word "hours" is often appended in U.S. military usage ("seventeen thirty hours"), though it's optional and rarely used in hospitals or aviation.

Midnight: 0000 or 2400?

Midnight is the one moment with two valid labels. 0000 marks midnight as the start of a new day, and is the standard form on digital clocks, schedules, and in most timekeeping systems. 2400 marks the same instant as the end of the previous day, and shows up where the day a time belongs to matters — "the bridge closes at 2400 Friday" unambiguously means the end of Friday, whereas "0000 Friday" means the moment Friday begins, a full 24 hours earlier. This converter, like most software, uses 0000 and treats 2400 as out of range. A practical convention many schedulers use to dodge the ambiguity entirely: write 2359 or 0001 instead of either form of midnight.

Who uses military time, and why

Any field where an AM/PM mix-up is expensive tends to adopt the 24-hour clock. Healthcare charts medications and vitals in 24-hour time because a dose recorded at "7:00" is dangerously ambiguous on a 12-hour clock — 0700 and 1900 are twelve hours apart, and shift handoffs happen around the clock. Aviation uses it for flight plans and air traffic control, usually pinned to Coordinated Universal Time (UTC, called "Zulu" in radio shorthand) so that crews crossing time zones agree on a single clock. The military runs operations across midnight and across the globe, where "see you at 8" is useless without more context. Emergency dispatch, railroads, and shipping logs use it for the same reason. For payroll, the format matters too: punch times written in 24-hour or military form subtract cleanly without AM/PM bookkeeping, which is why timesheet math is easier in 24-hour form — see the guide to calculating time card hours by hand for the full method.

Frequently asked questions